A torque sensor is known which has e.g., a Hall IC as a sensor for detecting a magnetic field molded in a resin and detects torque applied to a steering wheel of a vehicle based on variation in strength of a magnetic field detected by the Hall IC (see e.g., PTL 1).
The torque sensor disclosed in PTL 1 is provided with an input shaft connected to a steering wheel, an output shaft connected to a steered wheel, a torsion bar coupling the input shaft to the output shaft, a multipole magnet, a pair of multipolar yokes and two Hall ICs, and is configured that twisting of the torsion bar due to torque applied to the steering wheel causes relative rotation of the multipole magnet and the pair of multipolar yokes. A pair of annular magnetic collecting rings is arranged around the pair of multipolar yokes, and a magnetic collecting portion protruding in a radial direction is provided on each of the magnetic collecting rings at a circumferential position. The two Hall ICs are arranged between the magnetic collecting portion of one magnetic collecting ring and the magnetic collecting portion of the other magnetic collecting ring.
Where the multipole magnet rotates relative to the pair of multipolar yokes, the strength of the magnetic field detected by the Hall ICs is changed according to the relative rotation angle. Thus, a torque applied to the steering wheel can be detected based on this change in the magnetic field strength. The two Hall ICs are molded in a resin member together with the pair of magnetic collecting rings.